Brake



' May 31, 1932. BUGATT] 1,860,779v

BRAKE Filed Nov. 15, 1929 2 Sheets-Sheet 1 E. BUGATTI May 31, 1932.

v BRAKE Filed Nov; 13, 1929 2 Sheets-Sheet 2 Patented May 31, 1932 UNITED STATES E'ITORE FUGATTI, OF MOLSHEIM FRANCE BRAKE Application filed November 13, 1929, Serial No. 406,944, and in France November 13, 1828.

The present invention has for an'object a brake with automatic taking up of play. Said brake is characterized by a mechanism disposed preferably between the cam and the frame or support of. the control shaft of the cam, and arranged in a way to remain inoperative as long as the amplitude of angular dis placement of the cam from an initial position is less than a predetermined value, and to 1 modify the said initial position an amount corresponding to the play resulting from the wear of the lining in a wayto take up for this play. I a

The invention likewise includes an adjusting device for the brake pedal, permitting a conservation of .the normal stroke of said pedal irrespective of the play taken up.

The description which follows with respect,

. to the accompanying drawings given by way.

of exam le will allow the manner in which the invention is carried out to be well understood.

In the drawings-- a Fig. 1 is a longitudinal section partly in elevation of the brake device;

Fig. 1 is a detail in perspective of parts of the braking means;

Fig. 2 is a section alongthe line Fig. l;

Fig. 3 is a partial section along the line y-y of Fig. 1;

Fig. 4 is a modification of Fig. 1;

Figs. 5 and 6 illustrate how taking up for play is produced; and

Fig. 7 isa diagrammatic view of the whole of the brake device with a device for adjustingtthe position of the brake pedal.

eferring to the drawings the cams of the brake 1 of ordinary shape are controlledby A the levers 2. Between the body of the brake shoes 9, the cam 1 must travel an angular az-w of stroke which is larger, the fingers come in contact with the ed es 7? of grooves 7 and drive the washer4 in their rotation, which movement is possible from the shape of the teeth 4:, and 6 which allows release and rotation only in the direction of clamping of the cam. a

Upon releasing the brake,the cam 1 does not retake the initial position which it had before clamping, but an advanced position 0 with respect to the said initial position. This advance corresponds to the angular displace ment of the toothed washer 4 due to wear of the lining 9 of the shoes 9. The cam is arrested in this newposition by the end 7 b of c: the slots 7 against which abut the fingers 8. From this fact, the stroke of the brake cam remains always constant, irrespective of the wear of the lining.

According to the modified embodiment illustrated the toothed washer is replaced by a washer 10 having a tapered edge which arrests the cam 11 after its return to the nonclamping position by friction instigated by the springs 12 which apply the washer 10 .7 in its recess 13. I

It is well to notice that if the lever of the brake cam occupiesthe position A (Fig. 5)

.with the shoes having a fresh lining, it takes,

as soon' as the lining is used, the position B .(Fig. .6) which would cause the brake pedal to descend as fast as the taking up for play of the brake cams and at the same time diminish the available stroke for. braking. For compensating this descent, a screw 14 laced between the pedal 15 (Fig. 7) and the caring 16 permits bringing back the pedal to theposition that it had wlth the new shoes and to retainthe entire stroke for braking. n

I adjust the cables connecting the brake cam levers 2 with the control device therefor so that they remain slack as long as they are not operated. This arrangement prevents movementof the cams, during shakin of the springs or deformation of the chassis when the wheels pass overuneven parts. of fthe ground, which movements when repeated could cause wear of the shafts and of the cams or their bearing surfaces. As shown in Fig. 1 the shape of the teeth on part 4 9 and of the corresponding teeth 6 is such as a: p4erm1t one-way rotation only of mem-' r It will be obvious that many modifications 5 could be made in my device without departing from the s irit of the invention as comprehended wi the scope of the appended claims. v -Having described my invention what I claim as new and desire to secure byLetters Patent is: p

v 1.. An automatic compensating brake of the type described comprising a pair of brake shoes, camming means ,for' spreadin said brake shoes, an ope'ratin shaft for sai camming means, a bearing for said-shaft, an annular plate on said shaft having circular slots, resilient means for pressing said plate against said bearing, a series of ratchet teeth on said late next said bearing, corresponding ratc et teeth on said bearing en aging said first mentioned ratchet teeth, and gers on said camming means enga 'ng in said circular slots for the purpose escribed.

2. An automatic compensating brake of the type described comprising a pair of brake shoes, camming means for spreading said brake shoes, an operatin shaft for said camming means, a bearing or said shaft, an annular plate on said shaft having circular slots, resilient means for pressing said plate against said bearing, a series of ratchet teeth on said late ext said bearing, corresponding ratc ct teeth on said bearing engaging sald first mentioned ratchet teeth, fingers on said camming means engaging said circular slots, a manually operated pedal for said 1 camming means and an adjustable sto screw for said pedal adapted to compensate or loss of stroke as said' operating shaft is advanced.

In testimony whereof Ihave signed this specification.

- ETTORE BUGATTI. 

